Repair of lined pipes

ABSTRACT

Accordingly the invention resides in a method of selectively repairing the lining of a lined pipeline, said method comprising utilisation of a conveyance adapted to be receivable within the pipeline, said conveyance being adapted to be able to travel through the pipeline, said method further comprising introducing said conveyance into the pipeline, said conveyance comprising an inspection means, an excising means, a debris removal means and an application means, said method further comprising an identification step comprising causing the conveyance to travel along the length of the pipeline, inspecting the surface of the lining and identifying and locating damaged portions of the lining at locations along the pipeline, said method further comprising an excising step comprising moving said conveyance means along the pipeline and at the locations identified by the inspection excising the damaged portions of the lining from the pipeline, said method further comprising a debris removal step comprising causing said conveyance means to travel along said length of the pipeline to remove the debris and/or water left in the pipeline by the excising step, and said method comprising an application step comprising causing said conveyance means to travel along the said length of the pipeline and applying a fresh lining composition onto the lining to replace the excised portions of lining removed by the excising step. The invention also relates in a conveyance for effecting the selective repair of the lining of a lined pipeline according to the method described above

FIELD OF THE INVENTION

[0001] This invention relates to a method of refurbishing a linedpipeline and means to facilitate such refurbishment.

[0002] Throughout this specification the term “lining composition” shallbe taken as including any form of composition such as cement mortar,concrete, plastics materials (such as urethane or ethylene basedmaterials), epoxy materials, paints or like compositions which aresuitable for application to the internal surface of a pipeline for useas a protective lining.

BACKGROUND

[0003] A particular application of the invention relates to therefurbishing of water pipelines which have been lined with a liningcomposition.

[0004] In regard to water pipelines it has been conventional practice toprovide the pipelines with a cement lining in order to protect theinternal face of the pipeline from corrosion. However, a significantdifficulty arises with lined water pipelines when the liningdeteriorates and the protection which is offered by the lining isreduced. In the past, in circumstances where the lining has becomedegraded or damaged, it has been conventional practice to remove fromthe pipeline the damaged length of pipeline and replace it by a sectionof new pipeline or alternatively to completely remove all of theexisting lining and replace it with a fresh lining or alternativelypatch repair the localised lining failure manually. Each of theseexercises has proven to be unnecessarily expensive exercises.

[0005] However, it has been found that the existence of minor cracks orlike physical damage to the lining need not necessarily be indicativethat the lining is failing to provide its protection action since it hasbeen found that the alkaline environment provided by the lining seems toprovide a protective environment for the inner face of the pipeline.Furthermore, even after the chemical protection has been lost, thepresence of a physical barrier which is provided by the degraded liningseems to delay the progress of corrosion of the pipe. Therefore it isonly when the lining of the pipeline has been degraded such that it isunable to provide the desired chemical and physical protection of thepipeline that it becomes necessary to replace the lining. In addition ithas been found that the degradation does not usually occur uniformly butis only localised at particular locations in the lining (even inpipelines of considerable age) and the degree of localisation of thedamage or deterioration does not warrant the wholesale replacement of alength of pipeline or the wholesale refurbishment of the lining of thepipeline. Therefore the wholesale replacement of pipe or the lining canin many cases be unnecessary and extremely wasteful.

[0006] It is an object of this invention to provide a means and a methodwhereby the cement lining of a pipeline can be selectively refurbishedas required where such refurbishment can comprise the completereplacement of large sections of lining and/or partial refurbishment ofpatches of lining.

DISCLOSURE OF THE INVENTION

[0007] Accordingly the invention resides in a method of selectivelyrepairing the lining of a lined pipeline, said method comprisingutilisation of a conveyance adapted to be receivable within thepipeline, said conveyance being adapted to be able to travel through thepipeline, said method further comprising introducing said conveyanceinto the pipeline, said conveyance comprising an inspection means, anexcising means, a debris removal means and an application means, saidmethod further comprising an identification step comprising causing theconveyance to travel along the length of the pipeline, inspecting thesurface of the lining and identifying and locating damaged portions ofthe lining at locations along the pipeline, said method furthercomprising an excising step comprising moving said conveyance meansalong the pipeline and at the locations identified by the inspectionexcising the damaged portions of the lining from the pipeline, saidmethod further comprising a debris removal step comprising causing saidconveyance means to travel along said length of the pipeline to removethe debris left in the pipeline by the excising step, and said methodcomprising an application step comprising causing said conveyance meansto travel along the said length of the pipeline and applying a freshlining composition onto the lining to replace the excised portions oflining removed by the excising step.

[0008] According to a preferred feature of the invention said methodfurther comprises cutting a length of pipe from the pipeline at alocation to provide a gap in the pipeline at the location, locating asupport tray between the opposed ends of the remaining pipeline to spanthe lower portion of the gap and to provide a continuation of the lowersurface of the pipeline across the gap. According to a particularembodiment of the invention the pipeline is above the ground at thelocation. According to an alternative form of the invention the pipelineis buried at the location and the method further comprises exposing thelength of pipe at the location prior to the length of pipe being cutfrom the pipeline.

[0009] According to a preferred feature of the invention said conveyancemeans comprises a plurality of self propelled and self powered vehicleswhich comprise: at least one inspection vehicle for said inspectionstep; an excising vehicle for said excising step; at least one removalvehicle for said removal of debris step; and at least one applicationvehicle for said application step.

[0010] According to a preferred feature of the previous feature of theinvention at least some of the vehicles are adapted to be operatedremotely. According to one embodiment all of the vehicles are adapted tobe operated remotely. According to an alternative embodiment at leastone of the vehicles is adapted to be operated by an operator in-situ inthe pipeline and incorporates controls operable by the operator toeffect at least some of the operations of the vehicle. According to afeature of the alternative embodiment the at least one vehicle isprovided with a support to enable the operator to be supported by thevehicle. According to an alternative feature of the embodiment the atleast one vehicle is associated with an operator trolley which iscoupled to the at least one vehicle wherein the operator trolley isprovided with a support to enable the operator to be supported by theoperator trolley. According to a particular form the operator trolley isprovided with the controls.

[0011] According to a preferred feature of the invention said inspectionstep comprises causing the inspection vehicle to travel along theinterior of the pipeline and during such travel inspecting the liningwithin the pipeline, identifying locations of damaged or deterioratedlining and maintaining a log recording the axial position of saidlocation along the length of the pipeline, the radial location of thelocation around the pipeline, and the type of damage. According to oneembodiment of the invention the inspection step is conducted remotely.According to an alternative embodiment the inspection step involvesutilisation of an operator supported on the inspection vehicle, saidoperator being skilled in identifying the damaged or deterioratedportions of the lining, said identifying of damaged or deterioratedlining including the operator providing markings on the lining toindicate the locations.

[0012] According to a further preferred feature of the invention saidexcising step comprises utilisation of a remotely controlled nozzleconnected to a source of high pressure fluid whereby said nozzle is ableto be moved to direct a jet of said high pressure fluid, said remotelycontrolled nozzle being supported from the excising vehicle, said methodcausing the excising vehicle to travel along the interior of thepipeline and during such travel causing the nozzle to direct said jet ofsaid high pressure fluid onto the damaged lining at the locations inorder to remove the lining at said locations. According to oneembodiment the excising vehicle is associated with a remote controlstation which is provided with a display means and controls to enablethe remote operation of the vehicle and the nozzle from the controlstation by an operator.

[0013] According to a further preferred feature of the invention saiddebris removal step comprises causing a removal vehicle to travel alongthe interior of the pipeline and causing the removal vehicle to collectdebris from the interior of the pipeline as it travels. According to oneembodiment the removal step initially comprises causing a primaryremoval vehicle to travel along the interior of the pipeline, scoopinglarge items from the pipeline as it travels along the pipeline andconveying the items into a hopper associated with the primary removalvehicle. According to a further preferred feature of the embodiment saiddebris removal step further comprises causing a secondary removalvehicle to travel along the interior of the pipeline and causing thesecondary removal vehicle to brush the surface of the pipeline toextract smaller items of debris from the pipeline. According to afurther preferred feature of the embodiment said debris removal stepfurther comprises causing a tertiary removal vehicle to travel along theinterior of the pipeline and causing the tertiary removal vehicle towash and vacuum fine debris and water from the pipeline.

[0014] According to a preferred feature of the invention saidapplication step comprises causing the application vehicle to travelalong the length of the pipeline and causing the application vehicle toapplying the fresh lining composition to the locations at which thelining has been excised. According to one particular embodiment thelining composition is applied to a discrete location by sprayingutilising a directional nozzle. According to an alternative embodimentthe lining composition is applied around the internal circumference ofthe pipeline by the centrifugal application of the lining composition.According to a preferred feature of the embodiments the liningcomposition comprises a cementitious composition.

[0015] According to a preferred feature of the invention the methodfurther comprises the delivery of lining composition to the applicationvehicle during the application of the lining composition to thepipeline. According to one embodiment the lining composition isdelivered to the application vehicle by a delivery vehicle which isadapted to be able to travel through the pipeline and carry a quantityof lining composition to the application vehicle said delivery vehiclehaving a conveying means adapted to be able to convey the liningcomposition from the delivery vehicle to the application vehicle.

[0016] Accordingly the invention also resides in a conveyance for use inthe selective refurbishment of the internal cement lining of a pipelineaccording to the method described above, said conveyance comprising aplurality of vehicles capable of independently travelling along thepipeline for the purposes of inspection, excising damaged lining,removal of debris and application of a fresh lining composition, each ofsaid vehicles being configured such that their centre of gravity when inuse is below the central longitudinal axis of the pipeline and each ofsaid vehicles being self powered and self propelled.

[0017] According to a preferred feature of the invention said conveyancemeans comprises a plurality of self propelled and self powered vehicleswhich comprise: an inspection vehicle for said inspection step; anexcising vehicle for said excising step; at least one removal vehiclefor said removal of debris step; and at least one application vehiclefor said application step.

[0018] According to a preferred feature of the previous feature of theinvention at least some of the vehicles are adapted to be operatedremotely. According to one embodiment all of the vehicles are adapted tobe operated remotely. According to an alternative embodiment at leastone of the vehicles is adapted to be operated by an operator in-situ inthe pipeline and incorporates controls operable by the operator toeffect at least some of the operations of the vehicle. According to afeature of the alternative embodiment the at least one vehicle isprovided with a support to enable the operator to be supported by thevehicle. According to an alternative feature of the embodiment the atleast one vehicle is associated with an operator vehicle which iscoupled to the at least one vehicle wherein the operator vehicle isprovided with a support to enable the operator to be supported by theoperator vehicle. According to a particular form the operator vehicle isprovided with the controls.

[0019] According to a preferred form the inspection vehicle incorporatesa viewing means which comprises an illumination means and a viewingmeans comprising at least one camera adapted to facilitate inspection ofthe lining of the pipeline remotely.

[0020] According to a further preferred feature of the invention theexcising vehicle accommodates a nozzle which is supported to be capableof rotation about a longitudinal axis of said pipeline whereby saidnozzle is adapted to be able to direct a stream of high pressured fluidonto the lining to remove the lining from the pipe interior. Accordingto an embodiment of the invention the excising vehicle is associatedwith an umbilical incorporating a delivery conduit for said highpressure fluid. According to a further preferred feature of theinvention the excising vehicle further comprises an illumination meansand a viewing means comprising at least one camera to facilitate remoteinspection of the location being subjected to the action of said steamof high pressure fluid. According to one preferred feature the highpressure stream of fluid incorporates abrasive particles. According to afurther preferred feature of the invention the orientation of the streamto the surface of the pipeline can be adjusted. According to a furtherpreferred feature of the previous feature the excising vehicleincorporates a second nozzle which is directed onto the lower portion ofthe pipeline forward of the vehicle, wherein the second nozzle generatesa forwardly directed jet of fluid having a transverse extent.

[0021] According to a further preferred feature of the invention thedebris removal vehicle is adapted to travel along the pipeline andcollect the debris generated by the excising step from the pipelinewherein the vehicle is adapted to remove large and small items of debrisfrom the pipeline. According to a preferred feature of the invention thedebris removal vehicle comprises a plurality of vehicles comprising aprimary vehicle adapted to remove the large items of debris from thepipeline and a secondary vehicle for removal of the smaller items fromthe pipeline. According to a particular embodiment the debris removalvehicle also comprises a tertiary vehicle for the removal of finematerial from the pipeline. According to one embodiment the primaryvehicle comprises a scooping means, a conveying means and a hopper saidscooping means being adapted to scoop larger items of debris from thepipeline, the conveying means being adapted to convey the items from thescooping means to the hopper. According to the embodiment the secondaryvehicle comprises a brushing means, a vacuum extraction means and ahopper, said brushing means being adapted to brush the lower surface ofthe pipeline, the vacuum extraction means being adapted to convey thefine materials and water to the hopper. According to the embodiment thetertiary vehicle comprises a washing means, a vacuum extraction meansand a hopper, said washing means being adapted wash the fine materialsfrom the surface of the pipeline, the vacuum extraction means beingadapted to convey the fine materials and water to the hopper. Accordingto an alternative embodiment the debris removal vehicle comprises asingle vehicle incorporating scooping means, a brushing means, a washingmeans, a conveying means, a vacuum extraction means and a hopper, saidscooping means being adapted to scoop larger items of debris from thepipeline, the conveying means adapted to convey the items to the hopper,the brushing means adapted to brush the lower surface of the pipeline,the washing means adapted to wash fine materials from the surface of thepipeline, the vacuum extraction means associated with the brushing meansand washing means to convey materials dislodged by the brushing meansand the washing means to the hopper.

[0022] According to a further preferred feature of the invention theapplication vehicle comprises a hopper adapted to accommodate a quantityof said lining composition, a pump means for pumping said liningcomposition and an outlet which is capable of directing said liningcomposition onto the surface of the pipeline. According to oneembodiment a delivery means is provided between the hopper and the pumpand the delivery means is adapted to deliver the lining composition tothe pump. According to one embodiment the application vehicle includesan operator trolley which is adapted to accommodate an operator, whereinsaid outlet is supported from an operator trolley and is adapted to becontrolled by the operator. According to a preferred embodiment of theinvention the application vehicle is associated with a delivery vehiclehaving a hopper and a conveying means whereby said delivery vehicle canbe brought into abutting relationship with the application vehiclewhereby the conveying means can deliver lining composition from thehopper of the delivery vehicle to the hopper of the application vehicle.

[0023] According to a preferred feature of the invention the inspectionvehicle and excising vehicle comprise a single vehicle.

[0024] The invention will be more fully understood in the light of thefollowing description of several specific embodiments.

BRIEF DESCRIPTION OF THE DRAWINGS

[0025] The description will be more fully understood in the light of thefollowing drawings of which;

[0026]FIG. 1 is schematic side elevation of an above ground pipelinewhich has been prepared for the refurbishment procedure according to thefirst embodiment;

[0027]FIG. 2 is a schematic side elevation of the inspection vehicleaccording to the first embodiment;

[0028]FIG. 3 is a schematic side elevation of the excising vehicleaccording to the first embodiment;

[0029]FIG. 4 is a side elevation of the primary removal vehicleaccording to the first embodiment;

[0030]FIG. 5 is a side elevation of the secondary removal vehicleaccording to the first embodiment;

[0031]FIG. 6 is a side elevation of the tertiary removal according tothe first embodiment;

[0032]FIG. 7 is a schematic side elevation of an application vehicleaccording to the first embodiment; and

[0033]FIG. 8 is a side elevation of a delivery vehicle according to thefirst embodiment.

DETAILED DESCRIPTION OF SPECIFIC EMBODIMENTS

[0034] The first embodiment is directed to the refurbishment of an aboveground lined water pipeline. The embodiment has particular applicationto a pipeline which has an internal lining formed of a cementitiouscomposition.

[0035] It is an object of the embodiment to provide a means whereby thedamaged portions of the lining of a water pipeline can be selectivelyreplaced as required.

[0036] The method according to the embodiment comprises initiallycutting a section from the length of pipeline as shown at FIG. 1 tocreate a gap 10 between two opposed ends of the pipeline. In practice ithas been found appropriate to create a number of gaps 10 of the form asdescribed above and shown at FIG. 1, at spacings of approximately threeto four hundred metres apart, whereby the various stages of therefurbishment process (ie. inspection, excising, removal of debris andapplication) can be effected simultaneously at different locations alongthe pipeline.

[0037] The gap is filled by a tray 11 which is intended to provide acontinuation of the lower portion of the pipeline between the exposedends 12 of the pipeline which have been created by the creation of thegap. The tray is adapted at each end to be supported from each end 12 ofthe pipeline. In addition the tray is provided at an intermediateposition along its length with an opening in its lower face. Once thetray 11 has been located in position across the gap defined between thetwo ends of the pipeline a conveyance is then used for the purposes ofinspection of the lining of the pipeline, excising damaged portions ofthe lining, removal of the debris generated by the excising process andapplication of fresh lining to the excised portions. The conveyancecomprises a number of separate vehicles which are capable of travellingalong the length of the pipeline. As a result of the creation of anumber of gaps 10 the vehicles are only required to travel the length ofthe pipeline between the adjacent gaps.

[0038] The vehicles which comprise the conveyance of the embodimentcomprise:

[0039] an inspection vehicle 30 (shown at FIG. 2);

[0040] an excising vehicle 40 (shown at FIG. 3);

[0041] a primary removal vehicle 50 (shown at FIG. 4);

[0042] a secondary removal vehicle 60 (shown at FIG. 5);

[0043] a tertiary removal vehicle 70 (shown at FIG. 6);

[0044] an application vehicle comprising an operator trolley 80 a hoppervehicle 90 and a battery vehicle 84 (shown at FIG. 7); and

[0045] a delivery vehicle 100 (shown at FIG. 8).

[0046] Each of the vehicles comprise a lower chassis which is providedwith a set of wheels. In addition each of the vehicles are configuredsuch that the centre of gravity of the vehicle, when in use (includingconditions when they accommodate an occupant and/or are carrying aload), is lower than the central longitudinal axis of the pipeline. Itis by this location of the centre of gravity that the vehicles areprevented from spiralling around the walls of the pipeline and willremain in the lower portion of the pipeline.

[0047] In addition each of the vehicles are movable independently alongthe length of the pipeline and are independently powered and as, aresult they do not require utilisation of an external power source inorder to effect the movement along the pipeline. This is effected byeach vehicle having a set of driven wheels which are driven fromelectric motors which are operated from a control means which may beremote from the vehicle and/or may be provided on the vehicle. Accordingto the embodiment the front wheels of a vehicle are driven from oneelectric motor while the rear wheels are driven from another electricmotor. The power for each of the drive motors is derived from a batterypack which can be supported from the vehicle. If desired the batterypack may be carried by a separate vehicle (is battery vehicles 52 ofFIG. 4, 62 of FIG. 5, 72 of FIG. 6 and 84 of FIG. 7) where there isinsufficient space available on a particular functioning vehicle or itis in appropriate to locate the battery pack on a functioning vehiclegiven the function of the functioning vehicle.

[0048] In some instances the vehicle may comprise or incorporate anoperator trolley which is supported from a set of non-driven wheels andhas a chassis which is configured to provide a platform which willaccommodate an operator. In each case the operator trolley is coupled toa the respective functional vehicle which has a chassis which issupported by a set of driven wheels which are associated with drivemotors which are drivingly connected to the drive wheels. The functionalvehicle provides the motive force to enable the operator trolley totravel through the pipeline as well as all specialist equipment to meetthe functional requirements of the respective vehicle. In each case theoperator trolley is provide with the appropriate controls to enable theoperator to control the movement of the operator trolley through thepipeline and the functions of the vehicle with which the trolley isassociated. In some instances the operator trolley may be provided witha visual display unit screen, an illumination means and a viewing meansin the form of one or more cameras to facilitate the control of thevehicle with which the operator trolley is associated.

[0049] The method according to the embodiment initially comprisesinspecting the length of pipeline between adjacent gaps 10 in thepipeline. This is effected by utilisation of an inspection vehicle 30 asshown at FIG. 2 which comprises an operator trolley 20. which issupported from a set of non-driven wheels 21 and has a chassis which isconfigured to provide a platform which will accommodate an operator 31.The operator trolley is coupled to a traction trolley 32 which has achassis which supports a battery pack and is supported by a set of drivewheels 35 which are associated with drive motors 34 which are drivinglyconnected to the drive wheels 35. The traction trolley 32 provides themotive force to enable the inspection vehicle to travel through thepipeline. The forward end of the operator trolley is provided with ahand control 36 which can be manipulated by the operator 31 to effectthe controlled movement of the inspection vehicle along the pipeline. Inaddition the operator trolley 30 is associated with an illuminationmeans which is able to illuminate the walls of the pipeline tofacilitate the visual inspection of the pipeline by the occupant 31. Inaddition the operator trolley is associated with a communication means.If desired the inspection vehicle can include a viewing means in theform of one or more video cameras which can be used to provide a recordof the state of the pipeline prior to its refurbishment. In additionaccording to the embodiment the operator 31 when inspecting the pipelinewill physically mark the locations of the damaged portions of thepipeline for later identification during the excising operation.

[0050] Once the length of pipeline between two adjacent gaps 10 has beeninspected and the damage or degradation to the lining at the variouslocations along the pipeline have been identified and marked it is thennecessary to excise from the lining the damaged or degraded portions ofthe lining at each location. This is effected by utilisation of anexcising vehicle as shown at FIG. 3. The excising vehicle is operatedremotely such that is able to move independently along the length of thepipeline and as shown at FIG. 3 accommodates a battery pack 41 and a setof drive motors 42 which are drivingly connected to the wheels 43 of thevehicle 40. In addition the forward end of the vehicle 40 is providedwith an illumination means in the form of suitable lights and a set ofvideo cameras which are accommodated within a housing 44 and whichfacilitate the visual inspection of the lining in order to control,monitor and record the excising step. In addition the forward end of theexcising vehicle accommodates a excising nozzle 45 which is capable ofrotating about a longitudinal axis of the vehicle and which is directedgenerally radially. The excising nozzle 45 is intended to effect theremoval of the lining at the locations identified by the inspection stepand is capable of producing a jet of high pressure fluid which ifdesired can incorporate abrasive particulate materials to enhance itsaction. In addition the excising vehicle is provided with a washingnozzle 46 which is directed forwardly and axially from the forward endof the excising vehicle 40 and which can be adjusted to be directedobliquely at the surface of the pipeline. The washing nozzle 46 producesa spray which is capable of washing the surface of the pipeline. Theforward end of the excising vehicle 40 also accommodates a plurality ofdebris clearance nozzles 47 which are directed forwardly and downwardlysuch that it they are directed onto the surface of the pipeline ahead ofthe excising vehicle. The debris clearance nozzles 47 jointly produce ahigh pressure spray having a lateral dimension such that it is able toimpact upon debris generated by the excising process and drive itforwardly of the excising vehicle as the excising vehicle moves alongthe length of the pipeline.

[0051] The excising vehicle 40 is associated with a high pressure fluiddelivery conduit for the delivery of fluid to the excising nozzle 45,the washing nozzle 46 and the debris clearance nozzles 47. The excisingvehicle 40 is also associated with an umbilical which accommodateselectrical cables for controlling all of the functions of the excisingvehicle and transmitting the signals from the camera and any othersensors associated with the vehicle to the control room.

[0052] In use the excising vehicle is caused to travel along thepipeline and when it reaches a previously identified location of damagedlining, the excising nozzle 45 is moved to a position such that it isdirected towards the damaged portion and a jet of high stream fluid isthen directed towards the damaged portion in order to remove the damagedportion of lining. During this operation the action of the excisingnozzle 45 can be monitored through the camera to ensure that theexcising action is adequate. In addition as the excising vehicle 40moves along the length of the pipeline the surface of the pipeline iswashed by the washing nozzle 46 to at least partially remove slimesand/or loose particles from the surface. In addition the debrisclearance head 47 serves to drive any debris which is generated by theexcising operation forward of the excising vehicle 40 such that thedebris does not inhibit the movement of the excising vehicle along thepipeline. If desired the excising function, the washing function and thedebris clearance function of the excising vehicle may be effected inunison or independently as separate functions. In addition in the eventthat the amount of debris in the pipeline inhibits the progress of theexcising vehicle through the pipeline it may be necessary to extract theexcising vehicle from the pipeline and effect the removal of the debrisfrom the pipeline by at least partial utilisation of one or more of thedebris removal vehicles as described below.

[0053] Once the excising step has been completed or during the excisingstep it will become necessary to remove from the pipeline the debriswhich has been generated by the excising step. This is effected by useof at least one of the debris removal vehicles which are shown at FIGS.4, 5 and 6.

[0054] The debris removal vehicles comprise a primary removal vehicle 50as shown at FIG. 4 which is intended to remove large items of debrisfrom the pipeline, a secondary removal vehicle 60 as shown at FIG. 5which is intended to brush the lower surface of the pipeline to removesmaller items and a tertiary removal vehicle 70 as shown at FIG. 6 whichenables the collection of fine materials and residual water which hasbeen not collected by the primary and secondary removal vehicles. Eachof the removal vehicles is associated with an operator trolley 51, 61and 71 which are of a similar form to the operator trolley used with theinspection vehicle. Each operator trolley 51, 61 and 71 is able toaccommodate an operator and is provided with a hand control whereby theoperator is able to effect all of the functions of the respectivevehicle. In addition each removal vehicle is associated with a batterypack 52, 62 and 72 respectively which is supported upon its own wheeledchassis and which powers the drive motors for the wheels of the primary,secondary and tertiary removal vehicles 50, 60 and 70 respectively aswell as the motors associated with the conveying means (when present)and any other ancillary apparatus.

[0055] The primary removal vehicle 50 is provided with a forwardlyextending scoop 53 which is supported upon a forwardly extending frame54 which is pivotally supported from the forward end of the main body ofthe primary removal vehicle 50. A hydraulic ram or like extension meansis provided between the chassis and the frame 54 in order to control theelevation of the scoop 53 from the lower surface of the pipeline. Inaddition the scoop 53 is associated with a conveyor which comprises anendless belt 55 which extends along the length of the forwardlyextending frame and for a portion of the length of the body of theprimary removal vehicle 50 to terminate at a hopper 56 provided in theprimary removal vehicle 50. In use the primary removal vehicle is movedalong the pipeline with the scoop 53 in close engagement with the lowerface of the pipeline whereby large items of debris are picked up by thescoop and carried to the conveyor whereby they are then conveyed to thedebris hopper. The hopper 56 which is provided in the primary removalvehicle 50 is provided with at least one closure on its lower facewhereby the closure may be selectively opened to permit the contents ofthe hopper to be dumped. This is effected when the primary removalvehicle 50 is supported upon the tray 11 provided in the gap 10 betweenthe two ends of the pipeline 12 whereby the closure is located directlyover the opening 13 provided in the tray in order that the contents ofthe hopper are deposited onto the ground below the tray.

[0056] The secondary removal vehicle 60 as shown at FIG. 5 is providedat its forward end with a brushing unit comprising a brush 63 having aprofile corresponding to the profile of the lower portion of the pipeand which by its action is able to deliver debris from the floor of thepipeline to a hopper 65 provided within the body of the secondaryremoval vehicle 60. The secondary removal vehicle 60 is also providedwith a vacuum extraction means whereby the smaller debris not collectedby the brush is sucked through a duct 64 to a second hopper 66 providedwithin the body of the secondary removal vehicle. The hoppers 65 and 66are also provided with at least one closure on their lower face toenable the contents of the hoppers to be deposited from the hoppers whenthe secondary removal vehicle is located on the tray 11 located in thegap 10 between two ends 12 of the pipeline.

[0057] The tertiary removal vehicle 70 as shown at FIG. 6 comprises awashing and vacuum extraction unit whereby the excised portions of thepipe can be finally cleaned. The vehicle comprises a water reservoir 73which is connected through a pump 74 to an outlet nozzle 75 which isintended to direct a spray of water into the lower portion of the pipe.The outlet nozzle 75 is associated with a vacuum inlet 76 which isconnected to a hopper 77 whereby the water and entrained debriscollecting in the lower portion of the pipe can be picked up anddeposited into the hopper 76 supported on the vehicle. The hopper 77 isprovided with at least one closure in its lower face whereby the hoppercan be opened to enable the contents to be deposited from the hopperwhen the tertiary removal vehicle is supported upon the tray 11 in thegap 10 between the two ends 12 of the pipe.

[0058] As a result of the utilisation of the three debris removalvehicles the surface of the pipe can be thoroughly cleaned subsequent tothe excising action and in preparation for the application step.

[0059] The application step comprises the selective application of afresh lining composition to the locations at which the pre-existinglining has bee excised from the pipeline by the excising step. In orderto replace the damaged lining an application vehicle of the form asshown as FIG. 7 is utilised. The application vehicle comprises anoperator trolley 80 which is intended to accommodate an occupant andwhich has a hand control 81 to facilitate the controlled movement of theapplication vehicle along the pipeline. In addition the operator trolley80 is provided with an application means for the application of a liningcomposition onto the wall of the pipe. The application means cancomprise a spray nozzle 82 supported upon on a radial arm 83 which isable to rotate about an longitudinal axis of the pipeline and which canbe controlled in its movement and operation by the operator to effect alocalised application of the lining composition to the pipeline. Wherethe application step involves the wholesale application of a liningcomposition to a large area the application means may comprise a spinnerhead which is caused to rotate about a longitudinal axis and which hasan outlet from which the lining composition is delivered to be throwncentrifugally against the internal face of the pipeline to effect aspray pattern around the inner circumference of the pipeline.

[0060] The application vehicle also comprises a hopper vehicle 90 whichis supported in the pipeline by a set of driven wheels 91 which areassociated with drive motors. The hopper vehicle 90 accommodates ahopper for the lining composition which is connected to the applicationmeans through a delivery means in the form of an auger and through apump for the delivery of the lining composition to the applicationmeans. The application vehicle is also associated with a battery vehicle84 which is supported upon a wheeled chassis 85 and which is towedbehind the hopper vehicle 90.

[0061] The application vehicle is also associated with a deliveryvehicle 100 whereby the hopper 93 of the application vehicle can berefilled with the lining composition. The delivery vehicle 100 isassociated with an operator trolley 110 which accommodates an occupantwho is able to control all of the functions of the delivery vehicle. Inaddition the operator trolley 110 is provided with a visual display unitscreen which is associated with a camera and lighting means 103 providedat the forward end to the vehicle 100 whereby the operator is able todetermine the location of the delivery relative to the applicationvehicle when approaching the application vehicle.

[0062] The delivery vehicle 100 comprises a hopper 104 which is intendedaccommodate the lining composition. The hopper 104 is connected to apump through a feed auger 105 which is connected to a delivery pipe 106which extends forwardly from the delivery such that when the deliveryvehicle is in close abutment with the rearward end of the applicationvehicle the delivery pipe 106 is located to enable the liningcomposition being delivered from the delivery pipe will be depositedinto the hopper 93 of the application vehicle.

[0063] The delivery vehicle 100 enables the application vehicle to beused continuously in applying lining composition to the excised portionsof the lining at the locations at which the lining has been excisedwithout the need to return to the most adjacent gap 10 to be refilledwith lining composition.

[0064] The embodiment according to the invention provides a meanswhereby the life of an existing lined pipeline can be extended withoutthe need to effect wholesale replacement of the pipeline or completereplacement of lining of that pipeline which may include sound lining.Rather the method according to the embodiment involves theidentification of those portions of the pipeline which have sufferedsignificant deterioration, excising of those portions of the lining fromthe existing lining and then replacement of the excised portion withfresh lining composition.

[0065] According to a second embodiment of the invention the inspectionstep and the excising step are effected remotely by the use of the samevehicle. In the case of the second embodiment the camera of the excisingvehicle of the first embodiment is used to remotely inspect the state ofthe lining as the excising vehicle travels along the pipeline. On aportion of the lining being identified as being inadequate the excisingnozzle is activated to remove the lining so identified. In the case ofthe second embodiment the observation by the camera may be supplementedby other sensing means to assess the quality of the lining in order toassess its adequacy. In addition the state of the pipeline before and/orafter the excising action may be logged at the control station.

[0066] According to a second embodiment of the invention the removalvehicle may comprise a single vehicle which is able to achieve each ofthe functions of the primary, secondary and tertiary removal vehicles ofthe first embodiment.

[0067] According to a third embodiment of the invention the applicationvehicle may comprise a single vehicle which incorporates the combinedfeatures of the forward and rearward vehicles of the first embodiment.

[0068] According to a third embodiment the invention is applied to theselective refurbishment of the lining of an underground pipeline wherebythe pipeline is exposed at spaced positions to enable a gap of the formdescribed above in relation to the first embodiment to be created in thepipeline at each position and the pipeline to be treated in the mannerdescribed above in relation to each of the above embodiments. Accordingto an alternative embodiment openings are formed at each position ratherthan gaps.

[0069] Throughout the specification, unless the context requiresotherwise, the word “comprise” or variations such as “comprises orcomprising”, will be understood to imply the inclusion of a statedinteger or group of integers but not the exclusion of any other integeror group of integers.

[0070] It should be appreciated that the scope of the present inventionneed not be limited to the particular scope of the embodiments describedabove.

The claims defining the invention are as follows:
 1. A method ofselectively repairing the lining of a lined pipeline, said methodinvolving the utilisation of a conveyance adapted to be receivablewithin the pipeline, said conveyance being adapted to be able to travelthrough the pipeline, said conveyance comprising an inspection means, anexcising means, a debris removal means and an application means, saidmethod comprising introducing said conveyance into the pipeline, saidmethod further comprising: an inspection step which comprises causingthe conveyance to travel along the length of the pipeline; inspectingthe surface of the lining and identifying and locating damaged portionsof the lining at locations along the pipeline; an excising stepcomprising moving said conveyance along the pipeline and at thelocations identified by the inspection step excising the damagedportions of the lining from the pipeline; a debris removal stepcomprising causing said conveyance to travel along said length of thepipeline to remove the debris left in the pipeline by the excising step;and an application step comprising causing said conveyance to travelalong the said length of the pipeline and applying a fresh liningcomposition onto the lining to replace the excised portions of liningremoved by the excising step.
 2. A method of selectively repairing thelining of a lined pipeline as claimed at claim 1 which further comprisescutting a length of pipe from the pipeline at a position to provide agap in the pipeline at the location, locating a support tray between theopposed ends of the remaining pipeline to span the lower portion of thegap and to provide a continuation of the lower surface of the pipelineacross the gap.
 3. A method of selectively repairing the lining of alined pipeline as claimed at claim 2 wherein the pipeline is above theground at the position.
 4. A method of selectively repairing the liningof a lined pipeline as claimed at claim 2 wherein the pipeline is buriedat the position and the method further comprises exposing the length ofpipe at the position prior to the length of pipe being cut from thepipeline.
 5. A method of selectively repairing the lining of a linedpipeline as claimed at any one of the preceding claims wherein saidconveyance means comprises a plurality of self propelled and selfpowered vehicles which comprise: at least one inspection vehicle forsaid inspection step; an excising vehicle for said excising step; atleast one removal vehicle for said removal of debris step; and at leastone application vehicle for said application step.
 6. A method ofselectively repairing the lining of a lined pipeline as claimed at claim5 wherein at least some of the vehicles are operated remotely.
 7. Amethod of selectively repairing the lining of a lined pipeline asclaimed at claim 5 or claim 6 wherein all of the vehicles operatedremotely.
 8. A method of selectively repairing the lining of a linedpipeline as claimed at claim 5 or 6 wherein at least one of the vehiclesis provided with a support to enable the operator to be supported by thevehicle and is adapted to be operated by an operator in-situ in thepipeline and the vehicle incorporates controls operable by the operatorto effect at least some of the operations of the vehicle.
 9. A method ofselectively repairing the lining of a lined pipeline as claimed at claim8 wherein the at least one vehicle is associated with an operatortrolley which provides said support to enable the operator to besupported by the vehicle and said controls.
 10. A method of selectivelyrepairing the lining of a lined pipeline as claimed at claim 8 whereinthe at least one vehicle is associated with an operator vehicle which iscoupled to the at least one vehicle wherein the operator vehicle isprovided with a support to enable the operator to be supported by theoperator vehicle.
 11. A method of selectively repairing the lining of alined pipeline as claimed at claim 10 wherein the operator vehicle isprovided with the controls.
 12. A method of selectively repairing thelining of a lined pipeline as claimed at any one of the preceding claimswherein said inspection step comprises causing the inspection vehicle totravel along the interior of the pipeline and during such travelinspecting the lining within the pipeline, identifying locations ofdamaged or deteriorated lining.
 13. A method of selectively repairingthe lining of a lined pipeline as claimed at claim 12 wherein theinspection step is conducted remotely and a log is maintained to recordthe position of said locations in the pipeline and the type of damage.14. A method of selectively repairing the lining of a lined pipeline asclaimed at claim 12 wherein the inspection step involves utilisation ofan operator supported on the inspection vehicle, said operator beingskilled in identifying the damaged or deteriorated portions of thelining, said identifying of damaged or deteriorated lining including theoperator providing markings on the lining to indicate the locations. 15.A method of selectively repairing the lining of a lined pipeline asclaimed at any one of the preceding claims wherein said excising stepcomprises utilisation of a nozzle connected to a source of high pressurefluid whereby said nozzle is able to be moved to direct a jet of saidhigh pressure fluid over the surface if the lining, said remotelycontrolled nozzle being supported from the excising vehicle, said methodcausing the excising vehicle to travel along the interior of thepipeline and during such travel causing the nozzle to direct said jet ofsaid high pressure fluid onto the lining at the locations in order toremove the lining at said locations.
 16. A method of selectivelyrepairing the lining of a lined pipeline as claimed at claim 15 whereinthe excising vehicle is associated with a remote control station whichis provided with a display means and controls to enable the remoteoperation of the vehicle and the nozzle from the control station by anoperator.
 17. A method of selectively repairing the lining of a linedpipeline as claimed at any one of the preceding claims wherein saiddebris removal step comprises causing a removal vehicle to travel alongthe interior of the pipeline and causing the removal vehicle to collectdebris from the interior of the pipeline as it travels.
 18. A method ofselectively repairing the lining of a lined pipeline as claimed at claim17 wherein the removal step initially comprises causing a primaryremoval vehicle to travel along the interior of the pipeline, scoopingsaid large items from the pipeline as it travels along the pipeline andconveying the items into a hopper associated with the primary removalvehicle.
 19. A method of selectively repairing the lining of a linedpipeline as claimed at claim 17 or 18 wherein said debris removal stepfurther comprises causing a secondary removal vehicle to travel alongthe interior of the pipeline and causing the secondary removal vehicleto brush the surface of the pipeline to extract smaller items of debrisfrom the pipeline.
 20. A method of selectively repairing the lining of alined pipeline as claimed at claim 17, 18 or 19 wherein said debrisremoval step further comprises causing a tertiary removal vehicle totravel along the interior of the pipeline and causing the tertiaryremoval vehicle to wash and vacuum fine debris and water from thepipeline.
 21. A method of selectively repairing the lining of a linedpipeline as claimed at any one of the preceding claims wherein saidapplication step comprises causing the application vehicle to travelalong the length of the pipeline and causing the application vehicle toapplying the fresh lining composition to the locations at which thelining has been excised.
 22. A method of selectively repairing thelining of a lined pipeline as claimed at claim 21 wherein the liningcomposition is applied to a location by spraying utilising a directionalnozzle.
 23. A method of selectively repairing the lining of a linedpipeline as claimed at claim 21 wherein the lining composition isapplied around the interior circumference of the pipeline by acentrifugal application of the lining composition.
 24. A method ofselectively repairing the lining of a lined pipeline as claimed at claim21 or 22 or 23 wherein the method further comprises the delivery oflining composition to the application vehicle during the application ofthe lining composition to the pipeline.
 25. A method of selectivelyrepairing the lining of a lined pipeline as claimed at claim 24 whereinthe lining composition is delivered to the application vehicle by adelivery vehicle which is adapted to be able to travel through thepipeline and carry a quantity of lining composition to the applicationvehicle, said delivery vehicle having a conveying means adapted to beable to convey the lining composition from the delivery vehicle to theapplication vehicle.
 26. A method of selectively repairing the lining ofa lined pipeline as claimed at any one of the preceding claims whereinthe lining composition comprises a cementitious composition.
 27. Amethod of selectively repairing the lining of a lined pipelinesubstantially as herein described.
 28. A conveyance for use in theselective refurbishment of the lining of a lined pipeline according tothe method described above, said conveyance comprising a plurality ofvehicles capable of independently travelling along the pipeline for thepurposes of inspection, excising damaged lining, removal of debris andapplication of a fresh lining composition, each of said vehicles beingconfigured such that their centre of gravity when in use is below thecentral longitudinal axis of the pipeline and each of said vehiclesbeing self powered and self propelled.
 29. A conveyance for use in theselective refurbishment of the lining of a lined pipeline as claimed atclaim 28 wherein a plurality of self propelled and self powered vehicleswhich comprise: an inspection vehicle for said inspection step; anexcising vehicle for said excising step; at least one removal vehiclefor said removal of debris step; and at least one application vehiclefor said application step.
 30. A conveyance for use in the selectiverefurbishment of the lining of a lined pipeline as claimed at claim 29wherein at least some of the vehicles are adapted to be operatedremotely.
 31. A conveyance for use in the selective refurbishment of thelining of a lined pipeline as claimed at claim 29 and 30 wherein all ofthe vehicles are adapted to be operated remotely.
 32. A conveyance foruse in the selective refurbishment of the lining of a lined pipeline asclaimed at claim 29 and 30 wherein at least one of the vehicles isprovided with a support to enable the operator to be supported by thevehicle and is adapted to be operated by an operator in-situ in thepipeline and the vehicle incorporates controls operable by the operatorto effect at least some of the operations of the vehicle.
 33. Aconveyance for use in the selective refurbishment of the lining of alined pipeline as claimed at claim 32 wherein the at least one vehicleis associated with an operator trolley which provides said support toenable the operator to be supported by the vehicle and said controls.34. A conveyance for use in the selective refurbishment of the lining ofa lined pipeline as claimed at claim 32 wherein the at least one vehicleis associated with an operator vehicle which is coupled to the at leastone vehicle wherein the operator vehicle is provided with a support toenable the operator to be supported by the operator vehicle.
 35. Aconveyance for use in the selective refurbishment of the lining of alined pipeline as claimed at claim 34 wherein the operator vehicle isprovided with the controls.
 36. A conveyance for use in the selectiverefurbishment of the lining of a lined pipeline as claimed at any one ofclaims 29 to 35 wherein the inspection vehicle incorporates anillumination means and a viewing means which comprises at least onecamera adapted to facilitate inspection of the lining of the pipelineremotely.
 37. A conveyance for use in the selective refurbishment of thelining of a lined pipeline as claimed at any one of claims 29 to 36wherein the excising vehicle accommodates a nozzle which is supported tobe capable of rotation about a longitudinal axis of said pipelinewhereby said nozzle is adapted to be able to direct a stream of highpressured fluid onto the lining to remove the lining from the pipeinterior.
 38. A conveyance for use in the selective refurbishment of thelining of a lined pipeline as claimed at claim 37 wherein the excisingvehicle is associated with a remote control station which is providedwith a display means and controls to enable the remote operation of thevehicle and the nozzle from the control station by an operator.
 39. Aconveyance for use in the selective refurbishment of the lining of alined pipeline as claimed at claim 38 wherein the excising vehicle isassociated with a delivery conduit for said high pressure fluid and anumbilical providing connection between the control station and theexcising vehicle.
 40. A conveyance for use in the selectiverefurbishment of the lining of a lined pipeline as claimed at claim 37or 38 or 39 wherein the excising vehicle further comprises anillumination means and a viewing means comprising at least one camera tofacilitate remote inspection of the location being subjected to theaction of said steam of high pressure fluid.
 41. A conveyance for use inthe selective refurbishment of the lining of a lined pipeline as claimedat claim 37 or 38 or 39 or 40 wherein the high pressure stream of fluidincorporates abrasive particles.
 42. A conveyance for use in theselective refurbishment of the lining of a lined pipeline as claimed atclaim 37 or 38 or 39 or 40 or 41 wherein the orientation of the streamto the surface of the pipeline can be adjusted to effect various degreesof wash.
 43. A conveyance for use in the selective refurbishment of thelining of a lined pipeline as claimed at claim 37 or 38 or 39 or 40 or41 or 42 wherein the excising vehicle incorporates a second nozzle whichis directed onto the lower portion of the pipeline forward of thevehicle, wherein the second nozzle generates a jet of fluid having atransverse extent.
 44. A conveyance for use in the selectiverefurbishment of the lining of a lined pipeline as claimed at any one ofclaims 29 to 43 wherein the debris removal vehicle is adapted to travelalong the pipeline and collect the debris generated by the excising stepfrom the pipeline wherein the vehicle is adapted to remove large andsmall items of debris and/or water from the pipeline.
 45. A conveyancefor use in the selective refurbishment of the lining of a lined pipelineas claimed at claim 44 wherein the debris removal vehicle comprises aplurality of vehicles comprising a primary removal vehicle adapted toremove the large items of debris from the pipeline and a secondaryremoval vehicle for removal of the smaller items and/or water from thepipeline.
 46. A conveyance for use in the selective refurbishment of thelining of a lined pipeline as claimed at claim 45 wherein the debrisremoval vehicle also comprises a tertiary removal vehicle for theremoval of fine material and/or water from the pipeline.
 47. Aconveyance for use in the selective refurbishment of the lining of alined pipeline as claimed at claim 45 or 46 wherein the primary removalvehicle comprises a scooping means, a conveying means and a hopper saidscooping means being adapted to scoop larger items of debris from thepipeline, the conveying means being adapted to convey the items from thescooping means to the hopper.
 48. A conveyance for use in the selectiverefurbishment of the lining of a lined pipeline as claimed at claim 45or 46 or 47 wherein the secondary removal vehicle comprises a brushingmeans, a vacuum extraction means and a hopper, said brushing means beingadapted to brush the lower surface of the pipeline, the vacuumextraction means being adapted to convey the debris dislodged by thebrush and/or residual water to the hopper.
 49. A conveyance for use inthe selective refurbishment of the lining of a lined pipeline as claimedat claim 46 and any one of claims 47 and 48 as dependant from claim 44wherein the tertiary removal vehicle comprises a washing means, a vacuumextraction means and a hopper, said washing means being adapted to washdebris from the surface of the pipeline, the vacuum extraction meansbeing adapted to convey the debris and/or water to the hopper.
 50. Aconveyance for use in the selective refurbishment of the lining of alined pipeline as claimed at any one of claims 29 to 44 wherein thedebris removal vehicle comprises a single vehicle incorporating scoopingmeans, a brushing means, a washing means, a conveying means, a vacuumextraction means and a hopper, said scooping means being adapted toscoop larger items of debris from the pipeline, the conveying meansadapted to convey the items to the hopper, the brushing means adapted tobrush the lower surface of the pipeline, the washing means adapted towash fine materials from the surface of the pipeline, the vacuumextraction means associated with the brushing means and washing means toconvey materials dislodged by the brushing means and the washing meansto the hopper.
 51. A conveyance for use in the selective refurbishmentof the lining of a lined pipeline as claimed at any one of claims 29 to50 wherein the application vehicle comprises a hopper adapted toaccommodate a quantity of said lining composition, a pump means forpumping said lining composition, an outlet which is capable of directingsaid lining composition onto the surface of the pipeline.
 52. Aconveyance for use in the selective refurbishment of the lining of alined pipeline as claimed at claim 51 wherein a delivery means isprovided between the hopper and the pump and the delivery means isadapted to deliver the lining composition to the pump.
 53. A conveyancefor use in the selective refurbishment of the lining of a lined pipelineas claimed at claim 51 or 53 wherein the application vehicle isassociated with a delivery vehicle having a hopper and a conveying meanswhereby said delivery vehicle can be brought into abutting relationshipwith the fourth vehicle whereby the conveying means can deliver liningcomposition from the hopper of the delivery vehicle to the hopper of theapplication vehicle.
 54. A conveyance for use in the selectiverefurbishment of the lining of a lined pipeline as claimed at claim 51or 52 or 53 wherein the application vehicle includes an operator trolleywhich is adapted to accommodate an operator, wherein said outlet issupported from an operator trolley and is adapted to be controlled bythe operator.
 55. A conveyance for use in the selective refurbishment ofthe lining of a lined pipeline as claimed at any one of claims 29 to 54wherein the inspection vehicle and excising vehicle comprise a singlevehicle.
 56. A conveyance for use in the selective refurbishment of thelining of a lined pipeline substantially as herein described.